It sounds to me like you just have an air or a vacuum leak. This is very common on this engine. Check the PCV hose and system to be sure it is not leaking engine vacuum. Also, be sure that the baro reading is correct. This is done with a scan tool looking at the psi or HZ reading. In addition, be sure that the fuel pressure is 28 to 45 psi when the engine is running. Another thing would be to check the engine coolant
temp sensor as this can cause your condition too.
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